# Transverse-energy distributions at midrapidity in $p$+$p$, $d$+Au, and Au+Au collisions at \sqrt{s_{_{NN}}}=62.4--200~GeV and implications for particle-production models Abstract : Measurements of the midrapidity transverse energy distribution, d\Et/d\eta, are presented for p$+$p, d$+$Au, and Au$+$Au collisions at $\sqrt{s_{_{NN}}}=200$ GeV and additionally for Au$+$Au collisions at $\sqrt{s_{_{NN}}}=62.4$ and 130 GeV. The $d\Et/d\eta$ distributions are first compared with the number of nucleon participants $N_{\rm part}$, number of binary collisions $N_{\rm coll}$, and number of constituent-quark participants $N_{qp}$ calculated from a Glauber model based on the nuclear geometry. For Au$+$Au, $\mean{d\Et/d\eta}/N_{\rm part}$ increases with $N_{\rm part}$, while $\mean{d\Et/d\eta}/N_{qp}$ is approximately constant for all three energies. This indicates that the two component ansatz, $dE_{T}/d\eta \propto (1-x) N_{\rm part}/2 + x N_{\rm coll}$, which has been used to represent $E_T$ distributions, is simply a proxy for $N_{qp}$, and that the $N_{\rm coll}$ term does not represent a hard-scattering component in $E_T$ distributions. The $dE_{T}/d\eta$ distributions of Au$+$Au and $d$+Au are then calculated from the measured p$+$p E_T distribution using two models that both reproduce the Au+Au data. However, while the number-of-constituent-quark-participant model agrees well with the d$+$Au data, the additive-quark model does not.
Document type :
Journal articles
Complete list of metadata

http://hal.in2p3.fr/in2p3-00926179
Contributor : Marie Pelletier Connect in order to contact the contributor
Submitted on : Thursday, January 9, 2014 - 11:01:42 AM
Last modification on : Sunday, June 26, 2022 - 12:00:27 PM

### Citation

S. S. Adler, S. Afanasiev, C. Aidala, N. N. Ajitanand, Y. Akiba, et al.. Transverse-energy distributions at midrapidity in $p$+$p$, $d$$+$Au, and Au$+$Au collisions at $\sqrt{s_{_{NN}}}=62.4$--200~GeV and implications for particle-production models. Physical Review C, American Physical Society, 2014, 89, pp.044905. ⟨10.1103/PhysRevC.89.044905⟩. ⟨in2p3-00926179⟩

Record views